کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4458539 1620962 2006 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Speciation of heavy metals in cement-stabilized waste forms: A micro-spectroscopic study
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی اقتصادی
پیش نمایش صفحه اول مقاله
Speciation of heavy metals in cement-stabilized waste forms: A micro-spectroscopic study
چکیده انگلیسی

Cement-based materials play an important role in multi-barrier concepts developed worldwide for the safe disposal of industrial and radioactive waste in underground repositories. In this study, synchrotron based-techniques (micro X-ray spectroscopy (XAS) and micro X-ray fluorescence (XRF)) were used to investigate Co and Ni uptake by Hardened Cement Paste (HCP) with the aim of improving our understanding of the immobilization process of heavy metals in cement at the molecular level. For Ni and Co, XRF mapping revealed a highly heterogeneous element distribution as far as the concentration is concerned. The XAS studies further showed that Ni(II) forms predominantly layered double hydroxide (LDH) phases. In contrast to Ni, Co was found to be present in the oxidation states II and III. Co(II) is predominately incorporated into newly formed Co(II) hydroxide-like phases (Co(OH)2), Co-LDH or Co-phyllosilicates, whereas Co(III) tends to be incorporated into a Co(III)O(OH)-like phase or a Co-phyllomanganate.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Geochemical Exploration - Volume 88, Issues 1–3, January–March 2006, Pages 77–80
نویسندگان
, , , , , ,